Printed documents or labels may contain digital data encoded on them using schemes such as two-dimensional barcodes, DataGlyphs, or similar machine readable marks. Data encoded in such marks do not appear in human-readable form, and thus, cannot be easily inspected or read by a user. Typically, such machine readable marks cannot be read by a user without the aid of a machine, such as a data scanner and computer.
A user may be concerned about inclusion of private or confidential data in the document, especially data contained in the machine readable marks. For example, machine readable marks are capable of encoding sensitive information, such as social security numbers, account numbers, addresses, and the like. The user may want to base a decision about the use and disposal of documents or labels on full knowledge of all data contained in the document. For example, a user may wish to securely store or destroy a document or label containing private or confidential data once it has been used.
If the document contains a machine readable marks, the user cannot easily determine if the representations encode private or confidential data. The user must decode the data in the machine readable mark in order to determine its contents. However, some or all of data encoded in the marks may simply be an alternate from of data that is clearly visible in readable printed form. That is, the machine readable marks may only be intended to aid machine processing.
Since the machine readable marks may contain sensitive data, the user cannot make an accurate decision about use and disposal of documents or label that contain machine readable marks without first using a machine to read marks. This may be time consuming if the user has many documents or the document includes several marks. Decoding each mark would be unnecessary if the marks contain only public data or data that is clearly visible in readable printed form elsewhere on the document.
Accordingly, it may be desirable to provide methods and systems that allow a user or device to easily recognize whether or not data encoded in machine readable marks appear in human-readable form somewhere on the document.